Hydralazine Induced Lupus Nephritis

Renal involvement is uncommon in the hydralazine induced systemic lupus erythematosus. We conducted a retrospective study to identify patients with biopsy proven Hydralazine induced lupus nephritis. Material and Methods: In this retrospective study, patients who had a diagnosis of hydralazine-induced lupus and were on hydralazine prior to their diagnosis of biopsy proven lupus nephritis were included. Clinical and laboratory data were obtained from review of medical records. The median follow-up time was 12 months. Results: Medical records were reviewed between 2013 to 2017. Four patients had a diagnosis of biopsy proven hydralazine-induced lupus nephritis and were on hydralazine prior to their diagnosis. The median age was 68 years at the time of diagnosis. The majority of patients were Caucasian (75%). Three were female (75%) and three (75%) were exposed to hydralazine 100mg three times daily. All four patients had biopsy proven lupus nephritis (class II, III, IV, III/IV) with elevated serum creatinine and were positive for ANA (titer of 640-1280, homogenous pattern). Of the three patients tested, all were positive for anti-Histone antibody. Two patients had positive anti-dsDNA, and one of them had low C3 and C4. The level of Anti-dsDNA normalized at 3 months while low C3 in one patient persisted at 12months. All had negative C-ANCA and 3 of the 4 had positive P-ANCA. All had strong positive MPO titer and 2 of the 3 tested had positive PR3.In addition to withdrawal of hydralazine, all four patients were treated with steroids, hydroxychloroquine and mycophenolate mofetil. Two of four patients received PLEX and two received Cytoxan and hemodialysis. Conclusion: A timely diagnosis of hydralazine induced lupus nephritis can be critical. In addition to withdrawal of hydralazine, all patients also require aggressive treatment similar to idiopathic lupus nephritis.